During exercise, the human body produces heat by consuming energy. To evacuate this heat, the body regulates its internal temperature by keeping it stable. This thermal regulation is largely achieved through the evaporation of sweat. Thus, sweating is the mechanism by which the body releases heat to the exterior. However, evaporation of sweat during exercise leads to losses of water and electrolytes (salt and minerals) throughout physical activity. To maintain good performance and prevent health risks, it is essential that athletes adapt their hydration according to these losses.

Femme de profil qui court sur logo brassard Be One by BeLab.


Research has shown that there is an optimal window for
maintain a good level of hydration while improving performance
sports. For long-term physical activities, dehydration or
overhydration can lead to reduced performance and risks
for health, especially in hot environments or during exercise

A study conducted by physiologist Armstrong in 2021 indicated that a
dehydration 1-3% of body weight loss could be
considered acceptable for long-term performance. However,
it is essential to monitor this level of dehydration throughout
exercise to improve performance and reduce risk.

However, it is difficult to precisely monitor the evolution of losses
fluids during exercise using current techniques. Of
plus, the variability between athletes (genetics, body size, age, level
training) and the exercise conditions make it difficult to emit
universal recommendations.

It is therefore the evacuation of internal heat to the outside of the body which is at the origin of the phenomenon of sweating. This evaporation of sweat during exercise will cause water losses and electrolyte losses throughout physical activity.

Deux femmes et un homme qui courent dans un parc. Be One By BeLab.


Controlling fluid loss during exercise is a challenge for
sportsmen. Currently, the amount of sweat lost can be measured by weighing
the body before and after exercise, and sodium (salt) lost in sweat can
be analyzed in the laboratory using patches or other systems.

However, these techniques are difficult to apply during a
training or competition in real time. The Be One cuff offers
solution by making it possible to continuously measure the sweat flow and the evolution of
level of sodium chloride (NaCl) in sweat. Sodium and chlorine are
electrolytes that can be lost in large quantities during activity
physical, which can disrupt the balance of the body and cause
cramps in certain athletes whose sweat is particularly concentrated in

Les conseils de Be One pour une meilleure hydratation

L’application Be One utilise vos mesures de perte hydrique et de sodium pour vous conseiller sur votre hydratation pendant et après l’exercice en vous proposant de préparer une boisson personnalisée basée sur vos paramètres physiologiques, sur la durée de la séance et sur vos besoins en eau et en sodium.

Détail brassard noir Be One  By BeLab


Be One, with a patented microfluid collector, makes it possible to obtain a continuous flow of sweat over many hours (2h to 24h depending on the sport practiced) and, consequently, continuous precise analyzes of the sweat unlike the adhesive patches of the competition. Adhesive patches are limited by the time of use, criticized by the lack of reliability of analyzes (limited electronic system) without forgetting the problems of detachment and skin irritation.

Soon on Google Play and the App Store, and from early 2024 on Garmin and Fitbit.